a transmitter did not cause the airbag to deploy, but the concern about transceivers and air bags is the placement of the transceiver. Air bags EXPLODE when deployed, you do not want a radio shot at you if the air bag were to fire.

Using the vehicle's factory wiring to power an amateur transceiver is not a good idea. Nowadays, the wire gage (yes, that's the way they spell it) in cars is barely large enough to handle the load imposed upon it. It's a weight-saving thing.

If you hook into the wrong circuit, or induce enough RF into the circuit, there is a remote chance the airbag (they're not airbags obviously) could fire. About 8 years ago, Ford Motor Company issued a warning to dealers about wiring police radios in Ford cars. Apparently, there were several reported cases of airbag deployment caused by RFI.

If you look over the NHTSA's accident reporting site, and do a search, you'll find several instances where airbag deployment happened while in motion without actually hitting any thing. Whether or not these cases were caused by RFI would be conjecture. So, my simple question is, why take a chance. Wire your rig directly to the battery!

I must second the note about mounting radios (or anything else) in the airbag deployment zone. I have worked several accidents where serious injuries were sustained from items impacted by the airbag and propelled at GREAT FORCE into vehicle occupants. I have a set of pictures I took of one accident where the passenger side airbag took out a rear facing child restraint seat (no occupant; thank God) and then bounced off the seat and shattered the front windsheild. There was minimal damage to both vehicles except for that caused by the airbag. The child restraint seat was shattered. I use these pics in presentations on the importance of properly installing child restraint seats. I have seen advisories on installing various electrical equipment into vehicles, but most dealt with possible shorts or surges setting off airbags. I am not an expert on this though. I always use direct connect to the battery. The place that installs our lights, sirens, and radios sucks!! I have had three cars catch on fire due to faulty installations, once while on a traffic stop. The violator said he smelled smoke and looked back and my light bar was on fire. I called the fire department and continued to write the ticket. I figured if I was going to get into trouble for burning up another car, I might as well get a ticket out of it. We used to get blamed for anything that went wrong whether we had anything to do with it or not. I no longer trust anyone but myself to install any equipment. I can't change anything with my work vehicles, but my personal vehicles will never have that problem.

It would be possible to "roll" a car without the air bags deploying, since the activation mechanism senses very fast deceleration, as happens when you hit something. If you go into a roll without any serious deceleration, I can see how the mechanism wouldn't fire. Of course, the mechanisms probably vary nowadays -- I'm recalling the way the original sensors worked, which was a kind of pendulum device similar to what keeps seat belts/shoulder harnesses snug in a collision, but then lets you pull them away if parked.

Then, maybe they are supposed to deploy, but didn't because the Alfa was built during the afternoon Vino break...

The advice about keeping objects out of the path of explosion in the event of an air bag activation is good. I cringe when I see people using Velcro and stuff to hold their remote front panels for rigs, sometimes directly in the path of the potential bag explosion. It must hurt a lot to be hit in the mouth with a front panel at hundreds of feet per second.

SRS systems aren't going to be deployed by any kind of RF. The systems are set to respond to various sequentially-triggered sensors, all of which must agree in order to trigger the final switch, usually a powder-driven pyrotechnic switch, which then sends the signal to the SRS module to fire and deploy the restraint. It's all a combination of deceleration and force that the computers use to determine whether or not to deploy the restraint. "Airbags" do not explode, they deploy and the "bag" immediately deflates to aid egress from the vehicle. It is not uncommon for people to sustain superficial light burns from the hot gas exiting the bag via large vents.

Automakers have recalled vehicles in the past because of defects in the restraint module that cause a deployment or fire, but no amateur RF transmitter is going deploy the restraint. You would have to be operating on the same frequency as the digital electronics at high power to even come close to triggering one of the sensors. If the restraint deploys while you are driving, chances are you'd be able to stay in control of the car long enough to stop safely.

If, for some reason, hell freezes over and your radio trips a sensor out of sequence, the computer would automatically shut down the entire SRS system and a warning light would come on the dashboard somewhere. This light means that the system is fully "safed" and the restraints cannot deploy. It also means that the system requires service, which may be expensive if you're out of warranty.

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